Add support for CLUSTER LINKS command (#2504)

* feat: Adding support for Cluster Links Command

Co-authored-by: Anuragkillswitch <70265851+Anuragkillswitch@users.noreply.github.com>

cluster_test.go

@@ -677,6 +677,30 @@ var _ = Describe("ClusterClient", func() {
 			Expect(assertSlotsEqual(res, wanted)).NotTo(HaveOccurred())
 		})
 
+		It("should CLUSTER LINKS", func() {
+			res, err := client.ClusterLinks(ctx).Result()
+			Expect(err).NotTo(HaveOccurred())
+			Expect(res).NotTo(BeEmpty())
+
+			// Iterate over the ClusterLink results and validate the map keys.
+			for _, link := range res {
+
+				Expect(link.Direction).NotTo(BeEmpty())
+				Expect([]string{"from", "to"}).To(ContainElement(link.Direction))
+				Expect(link.Node).NotTo(BeEmpty())
+				Expect(link.CreateTime).To(BeNumerically(">", 0))
+
+				Expect(link.Events).NotTo(BeEmpty())
+				validEventChars := []rune{'r', 'w'}
+				for _, eventChar := range link.Events {
+					Expect(validEventChars).To(ContainElement(eventChar))
+				}
+
+				Expect(link.SendBufferAllocated).To(BeNumerically(">=", 0))
+				Expect(link.SendBufferUsed).To(BeNumerically(">=", 0))
+			}
+		})
+
 		It("should cluster client setname", func() {
 			err := client.ForEachShard(ctx, func(ctx context.Context, c *redis.Client) error {
 				return c.Ping(ctx).Err()

command.go

@@ -4246,3 +4246,92 @@ func (cmd *KeyFlagsCmd) readReply(rd *proto.Reader) error {
 
 	return nil
 }
+
+// ---------------------------------------------------------------------------------------------------
+
+type ClusterLink struct {
+	Direction           string
+	Node                string
+	CreateTime          int64
+	Events              string
+	SendBufferAllocated int64
+	SendBufferUsed      int64
+}
+
+type ClusterLinksCmd struct {
+	baseCmd
+
+	val []ClusterLink
+}
+
+var _ Cmder = (*ClusterLinksCmd)(nil)
+
+func NewClusterLinksCmd(ctx context.Context, args ...interface{}) *ClusterLinksCmd {
+	return &ClusterLinksCmd{
+		baseCmd: baseCmd{
+			ctx:  ctx,
+			args: args,
+		},
+	}
+}
+
+func (cmd *ClusterLinksCmd) SetVal(val []ClusterLink) {
+	cmd.val = val
+}
+
+func (cmd *ClusterLinksCmd) Val() []ClusterLink {
+	return cmd.val
+}
+
+func (cmd *ClusterLinksCmd) Result() ([]ClusterLink, error) {
+	return cmd.Val(), cmd.Err()
+}
+
+func (cmd *ClusterLinksCmd) String() string {
+	return cmdString(cmd, cmd.val)
+}
+
+func (cmd *ClusterLinksCmd) readReply(rd *proto.Reader) error {
+	n, err := rd.ReadArrayLen()
+	if err != nil {
+		return err
+	}
+	cmd.val = make([]ClusterLink, n)
+
+	for i := 0; i < len(cmd.val); i++ {
+		m, err := rd.ReadMapLen()
+		if err != nil {
+			return err
+		}
+
+		for j := 0; j < m; j++ {
+			key, err := rd.ReadString()
+			if err != nil {
+				return err
+			}
+
+			switch key {
+			case "direction":
+				cmd.val[i].Direction, err = rd.ReadString()
+			case "node":
+				cmd.val[i].Node, err = rd.ReadString()
+			case "create-time":
+				cmd.val[i].CreateTime, err = rd.ReadInt()
+			case "events":
+				cmd.val[i].Events, err = rd.ReadString()
+			case "send-buffer-allocated":
+				cmd.val[i].SendBufferAllocated, err = rd.ReadInt()
+			case "send-buffer-used":
+				cmd.val[i].SendBufferUsed, err = rd.ReadInt()
+			default:
+				return fmt.Errorf("redis: unexpected key %q in CLUSTER LINKS reply", key)
+			}
+
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}

commands.go

@@ -422,6 +422,7 @@ type Cmdable interface {
 	PubSubShardNumSub(ctx context.Context, channels ...string) *MapStringIntCmd
 
 	ClusterSlots(ctx context.Context) *ClusterSlotsCmd
+	ClusterLinks(ctx context.Context) *ClusterLinksCmd
 	ClusterNodes(ctx context.Context) *StringCmd
 	ClusterMeet(ctx context.Context, host, port string) *StatusCmd
 	ClusterForget(ctx context.Context, nodeID string) *StatusCmd
@@ -3497,6 +3498,12 @@ func (c cmdable) ClusterSlots(ctx context.Context) *ClusterSlotsCmd {
 	return cmd
 }
 
+func (c cmdable) ClusterLinks(ctx context.Context) *ClusterLinksCmd {
+	cmd := NewClusterLinksCmd(ctx, "cluster", "links")
+	_ = c(ctx, cmd)
+	return cmd
+}
+
 func (c cmdable) ClusterNodes(ctx context.Context) *StringCmd {
 	cmd := NewStringCmd(ctx, "cluster", "nodes")
 	_ = c(ctx, cmd)